Tension-adjusting device for counterbalance-springs.



A.' K. TERNSTEDT. V TENSION ADJUSTING DEVICE FORCOUNTEHBALANCE SPRINGf.

APPLICATioN FILED 1111Y|1.1s15` 1,215,589. Patented 11911.13, 1917.1

2 SHEETS-*SHEET I.

Qq. SM2

Kxmwm N IN1/EN Ton l A, K.TEHNS1EDT. TENSION ADIUSTING DEVICEV FOR COUNTERBALANCE SPRINGSl APPLICATION FILED IULY I?, 1915- 1,215,589.N

l Patented Feb.z 13

hva/Enron 2 anims-SHEET 2.

STATES PATENT OFFICE. j

ALVAB K: TERNETEDT, F IllEW YORK, N. Y., ASSIGNOR TO PERFECT WINDOW` REGU- LATOB COMPANY, OF NEVI` YORK, N. Y., A CORPORATION OF MA INE.

IIlllll's05W-AS1)JTTS'ILIlil'lirv DEVICE FOR COUNTEEBLANCE-SPRINI S.

l al To all'wlwm :it may concern.'

' Beit known that I, Aman K. TERNsTnnT, a subject/of the King of Sweden, and a resldent of New York, in the county of New i. -Yorkand State of New York, have invented certain newand'useful Improvements in f" Tension-Adjusting Devices for Counterbalance-Sp gs, of which the followlng `1s a specification. 1 'Myf resent invention relates to a yde vlce or inecEanism whereby the tension of springs to counterbalance weight in a reciproing mechanism .may be adjusted.l

1&.amechanism whereby the tension of the may be varied without the necessity of disassembling or taking apart any of the mechanism. i

The invention is particularly 4useful in and adaptable for window' regulator con- `etructioms whereinv the window is raised and flowered by a driving mechanism comprisusually a chain and sprocket device einjxgiying a coil `sprin used to counterballMance the weight of t e window and assist 2in raising it. The invention is herein shown and described as applied to a window regulator of the'type Set forth in my prior aplication for patent for window operating an vi filed Dec. v19, 1911,' ser. No. 666359,

a l butv it will be understood that it may he emplayed in other types of window regulators as Well` as other mechanism.wl'ierein a part y such as a `window or sash is recita-mated "I5 and provided with a counterlmlancing spring l:for taking* the weight of the part or assist in moving it without departingll from the '.spirit of the invention. The invention consists in the` new and .10' useful mechanism whereby the tension ot' a counterbalance spring may be varied as well as in the combinations of parts and details ofA construction hereinafter more partir-,u-

larly described and thenspecified in the.

claims.

VIn the accompanying drawings Figure 1 is a front elevationof a window raising and lowering mechanism having luy present inl vention embodied therein.

-I `ig. 2 is an enlarged front elevation of the lowersprocket of the mechanism shown 1n Fig. 1 i

Patented Fl el). 13.1917.

Application fusa July 17, 19155 seriainaaos'z. i

`Fig. 3 is a vertical transverse -section taken on .the line 3-3 Fig; 2.

Fig. 4 is a partialsection and side elevation similar to Fig. 3 but shoving the parts in unlocked position.v

Fig. is a section through the sprocket wheel taken on the line Fig.

Fig. (5 is an elevation, parts being broken away.y of the sprocket wheel shown in Fig;

2 but illustrating the'reverse aide fron'i 'that shown 1n that figure. l

Fig. 7 1s a perspectlve view of the key y used to rotate one part of the sprocket when ,The object of the invention is to provide i adjustingr the tension of the spring.

'Referring to Fig. 1, the lower part of the 1 window or part reciprocated is indicated at driving chain 8 passing over tic sprockets 4 n and 7. The chain 8 is connect .al to the window by means oi a pin 9 engaging in a slot 10 of aplate 1.1 secured to aid depending from the window. B v rotating a handle 12 connected to the sprocket 4 the chain 8 is caused to travel around the Sli rockets fand 7 and the window is raised or lowered according to tlic direction of rotation given the handle. '.lhesr parts being fully described in luy aforementioned `)rior application any further description he 'ein is deen'led unnccessa ry. i

AccordingT to the )')resent innntion in the preferred manner ot' cari-yimgr it into effect,

the lower sprocket 7 con'il'n-isfs two parts,'

one part 1P being;r dish-shaped and provided with teeth 14 around its peripl eryengaging lug` 17 formed out ofthe material of the cover plate 15 by cutting a tongue therein and bending it laterally to the plane ofthe.l

cover while the other end ofthe spring is' se= cured to a similarly formed lug 18 integral I ner to be presently described.

When the window is lowered the spring 16 is wound up and stored with energy so that on raising the window it will unwind and assist in raisingv it by balancing its weight. In assembling the raising and lowering mechanism, the spring 16 is given an initial tension of an amount deemed necessary to vbalance the weight of the window but it frequently happens that after installing and operating the mechanism it is found that the tension of the spring is not correct to prop erly balance the window owing to various reasons such as variation in weight of windows, greater or less resistance in the guiding channels, &c. To meet this condition it lis necessary to adjust the tension of the spring. This adjustment is made according to this invention without removing any of the parts or disturbing the mechanism as will be apparent from the following description.

19 indicates a ball race forming a hub on which the-toothed disk 13 rotates, a set of balls 20 being interposed between the hub and a flange of the disk. The ball race 19 is securely fastened to the cover plate 15 by screws 21.

'The bar 5 is provided with a hole 22 into Jwhich any one of a` plurality of annularly arranged projections 23 on the face of the cover plate 15 is adapted to tit so that when the cover is brought into such -position that a projection 23 enters the hole 22 and the' cover fastened in this position, the cover and the hub 19 are locked to the supporting bar 5 andare immovable but stillthe toothed disk 13 ,is left free to rotate on the hub when the chain 8 is caused to travel. By

vproviding ay plurality of projections 23 closely spaced, the cover 15 can be lockedl in most any `desired position and When the projections are arranged in a complete circle as shown a coperating hole 22 is providedv in the bar 5 to receive the projection diametrically opposite the one in the hole 22.

24 indicates a locking keypassing through the ball race hub 19, cover 15 and bar 5 and is provided with a. head 25 bearing againstl the face of the hub 19. The other end of the key is threaded and provided with a nut 26 whereby the hub 19, cover 15 and supporting bar 5 are secured together and when `a projection 23 is in the hole v22 the cover 15, to which the inner end of the spring is attached, is locked to the support 5 andv immovable.

Upon loosening the nut 26 the sprocket wheel in its entirety can be forced laterally 'for the insertion of a screw-driver.

slight distance therefrom.

these lugs or stops is to prevent the springbeing wound so tight that it will bind the tion.

into the position shown in Fig. 4 in which position the projections 23 are out of the holes and 22 and the cover l15 and therefore the inner end of the spring 16 may be rotated in any desired manner. The toothed disk 13 and therefore the outer end. of the spring being held by the position ofthe window and cham 8 any rotation given the cover will vary the tension of the spring either inv cover, I preferably form two diametrically opposed lugs 27 on the shank of the key 24 and provide a slot 28 in the end of the shank The lugs 27 fit into suitably formedrecesses 29 iu the liub 19 and cover .15 and when the projections 23 have been removed from their holes in the bar 5, a screw-driver in the slot 2S readily rotates the hub and cover by means of the lugs 27 on the key. It will thus -beseen that the tension of the spring formed out of the material ofthe cover 15 and in such position that they are annularly arranged around the ball race 19 at a.

ball race. i

`It will be understood that the invention is not limited to use in constructions of the type shown and described nor to the specific arrangements shown for carrying the invention into effect except as may be specified in the appended claims.

What I claim as my invention is 1. In a mechanism of thel character described, the combina-tion of a movable part,

means for reciprocating said part and comprising a two-part wheel, a fixed support on which said wheel is rotatably mounted and a coil spring having an end connected to each part of said wheel, an annularly arranged pin and slot devicefor adjustably securing one part of said wheel to said s upport and a key forrotating said part and clamping it to said support in adjusted Pos1.'

2. In a mechanism of the character described, the combination with the window,

of raising and lowering means for the same fand embodying a two-part Wheel, a .coil spring having one of its ends connected to one part of said Wheel and its other end t0 The object of the other part, one part ofsaid wheel being operated by said means and the other being secured to a lixedsupport by a pin and slot connection and a key by which said part may be rotated and clamped to its support..

3. In a mechanism of the character described, the eombinatin With the Window, of a chain drive for operating the same and embodying a two-part sprocket wheel one part of which is operated by the chain and j the other partv being provided with a plate of achain drive for op arating the saine and embodyin a two-part sprocket wheel one part of vv ich is operaned by the chain and the other part being p rovided with a plate and a hub on which said chain part rotates, 4 a fixed support for saic wheel, an annularly arranged pin a'nd slot device whereby said late may be held t0 sa .d support at a num` er of adjusted positions, a coil spring havj ing one of itsends conn acted to one part and its other end to the other part of said wheel -and a key adapted to r1 ltate said plate independent of the sprocke; part of said Wheel to adjust the tension oi? said spring and toA also clamp said plate in adjusted position to its support.

'Signed at New Yor t, in the county of New York and State of New York, this 12th day of July, A. D. 1915 ALVAR l. TERNSTEDT. Witnesses:

REMINGTON Soo'l r, IRENE LEFKOWITL 

